Sex while fertile during cycle

I’ve never had sex before until the other day, we didn’t use protection & used the pull out method.. bad idea, i know. So i was super stress the next day but didn’t know what to do. And we ended up doing the same thing again the next night. So this morning i took the “Take Action” (plan b) pill. But this afternoon we did it again, I’m so scared that I’m going to be pregnant. I have really bad heartburn and my stomach is cramping but i don’t know what to do.